Comtech EF Data CDM-760, Инструкция по установке и эксплуатации

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Front Panel Operation Revision 4
CDM-760 Advanced High-Speed Trunking Modem MN-CDM760
6–55
6.2.3.2.2 (Monitor: Stored-Events) Clr (Clear Event Log Buffer)
Event 001:001 16:21:58 25/04/14 (

 )
Info:Log ERASED Clr:Y
Use the  arrow keys to select Y (Yes) to clear the Stored Events buffer. The default is N
(No). Press ENTER to clear the buffer, or press CLEAR to back out of the command and return to
the previous menu.
If there are faults present on the unit at this time, the modem will again time-stamp the faults
and generate new log entries.
6.2.3.3 (Monitor:) ACM (Adaptive Coding and Modulation Parameters)
Tx Modcod=8PSK 8/9 R20.0 db
Rx Modcod=8PSK 8/9 L19.9 db
This
read-only
screen provides the active ACM Mode information:
Parameter Description
Tx Modcod Displays the Tx ModCod.
RemEsNo Displays the EsNo reported by the remote modem.
Rx Modcod Displays the Rx ModCod.
LocEsNo Displays the EsNo of the local unit.
6.2.3.4 (Monitor:) Rx-Params (Rx Parameters)
When the demodulator is not locked, this
read-only
screen appears as follows:
Demodulator
Unlocked RxLevel= dBM
Otherwise:
Rx-Params: EsNo=>23.5 dB ⌂F=+005.0 kHz
ModCod: QPSK 1/2 RxLevel= -31dBM
Note the following:
Parameter Description
Es/No
The value of the Es/No calculated by the demodulator. Es/No is the Energy per Symbol
received (Es) divided by the Noise Spectral Density (No). Note that the Es/No reading assumes
that a linear, non-distorted carrier is being received. If a carrier is operating at or near saturation
and there are nonlinear distortions, the Es/No reading may be inaccurate, especially when
demodulating 16APSk and 32APSK carriers.